PELVIC INFLAMMATORY DISEASE: WHAT IT IS AND HOW IT AFFECTS FERTILITY

Have you ever wondered why sexually transmitted infections (STIs) can lead to fertility problems? An important part of the answer is pelvic inflammatory disease (PID). PID is an infection of the vagina and the upper genital tract. It affects millions of women worldwide every year. 12.5% of women experience infertility after PID, and about 25% will develop chronic pelvic pain.

What is pelvic inflammatory disease (PID)?

PID, also known as an "ascending" infection, starts in the lower genital tract (vagina and cervix) and progresses to the upper genital tract (fallopian tubes, uterus, ovaries) as it spreads. How PID is classified depends on how it presents, whether it persists and whether a clinical cause has been identified:

• Acute PID: When symptoms appear suddenly or severely, it is defined as acute PID. It can cause both long-term and short-term symptoms, such as pelvic and abdominal pain, infertility and an increased risk of ectopic pregnancy.
• Subclinical PID: When PID is largely asymptomatic or presents atypically, it is called subclinical PID. It is often diagnosed when there are markers of pelvic inflammation, such as fallopian tubes blocked by scarring, disease or damage.
• Recurrent PID: Multiple episodes of PID can occur if the initial infection is not adequately treated or if the patient is reinfected with a primary infection.

What causes PID?

In at least 85% of cases, PID is caused by untreated chlamydia and gonorrhoea — two of the most common sexually transmitted infections (STIs). The remaining 15% of cases can be caused by a mix of other types of bacteria that have travelled up to the reproductive system and caused infection, such as Mycoplasma genitalium bacteria (a less common STI) and the pathogens that lead to bacterial vaginosis (the most common vaginal infection). Once a woman has had pelvic inflammatory disease, the damage caused by the infection can make her more vulnerable to future infections in the same area, further increasing the risk of infertility.

What are the symptoms of PID?

While subclinical PID often causes no symptoms at first, or only atypical, non-disruptive ones, acute PID is more likely to have clinically measurable symptoms. Unfortunately, this means that subclinical PID is more likely to go unnoticed.

Common symptoms of PID include:

• Pain in the lower abdomen
• Fever
• "Unusual" vaginal discharge with an odour
• Pain and/or bleeding during sex
• A burning sensation when urinating
• Bleeding between periods

Can PID have long-term, chronic effects?

Complications caused by PID include chronic pelvic pain, infertility, ectopic pregnancy and a high susceptibility to PID recurring. These complications are usually linked to damage and scarring of the reproductive organs and prolonged inflammation, including the following:

• Formation of scar tissue both outside and inside the fallopian tubes, which can lead to tubal blockage (associated with tubal factor infertility)
• Ectopic pregnancy (a pregnancy outside the uterus), which can be life-threatening
• Infertility
• Long-term pelvic/abdominal pain
• Tubo-ovarian abscess
• Hydrosalpinx: blockage and swelling of the fallopian tubes, a leading cause of tubal factor infertility (TFI).
• Being unable to get pregnant is often the first noticeable symptom, and this condition also has a negative effect on IVF outcomes.

How is PID diagnosed and treated?

PID is diagnosed with a pelvic examination, tests for sexually transmitted infections and tests for other infections. Tests may include swabs of the genital tract, blood samples, ultrasound scans and biopsies.

• A positive swab result confirms PID, but a negative swab result does not necessarily mean that PID is absent.
• Mild and moderate PID is usually treated with antibiotics. More severe and long-standing cases may require surgery, drainage of an abscess or an extended course of antibiotics.

Does PID affect fertility?

Although PID is treatable, the scarring it can cause in the reproductive tract, and sometimes the resulting infertility, often are not. Both acute and subclinical PID can lead to infertility by damaging the reproductive organs, causing blockages or disrupting reproductive processes. Some of this damage, for example to the microscopic cilia that line the fallopian tubes, is not visible to the naked eye. The effects of PID-related infertility can be difficult to treat, as the structural changes in the reproductive tract that PID sets in motion (such as tubal blockage due to scar tissue) are usually permanent. About 15% of female infertility is estimated to be related to PID. This becomes more likely once the infection has spread beyond the cervix and when there is permanent damage to the fallopian tubes, such as loss of ciliary action, fibrosis and tubal blockage.

Risk factors for PID-related infertility

Among the causes of PID, chlamydia appears to carry the greatest risk of infertility, because it is often asymptomatic. Some studies suggest that this could also be linked to individual immune responses to chlamydia and a stronger inflammatory reaction. Infertility becomes significantly more likely after either subclinical or clinical PID.

The risk of infertility increases when:

• Care for PID is delayed
• There have been more episodes of PID
• The infection is more severe
• Damage to the fallopian tubes results:

Can you have PID while you are pregnant?

Although uncommon, when PID coincides with pregnancy it is most likely to occur in the first trimester. If it is detected early, it can still be treated with antibiotics, most likely intravenously (although some types are best avoided during pregnancy). However, PID during pregnancy is still a risk factor for serious complications, including an increased risk of: pregnancy loss; ectopic pregnancy, especially if PID was present at conception; preterm birth; and maternal death in severe cases, particularly when an untreated ectopic pregnancy caused by PID leads to rupture of the fallopian tube and dangerous internal bleeding. PID can also occur as a postpartum infection within six weeks of giving birth, usually as inflammation of the lining of the uterus. This is more likely after a caesarean section, with a prevalence of only 1–3 in 100 women who give birth vaginally.

Can PID be prevented?

All sexually active women are potentially at risk of PID, although there are steps you can take to limit your exposure. If you are sexually active and not yet trying to conceive, using barrier methods during intercourse is an important preventive step. People who ovulate and whose partners use condoms consistently and correctly are less likely to develop recurrent PID or infertility. Although it does not provide complete protection, condom use can reduce the likelihood of infection by 30–60%.

Screening

Importantly, the Centers for Disease Control and Prevention recommends that all healthcare providers screen:

• All women who are sexually active
• Those who have a new sexual partner
• Those who have more than 1 sexual partner
• Those who have a sexual partner with concurrent partners
• Those who have a sexual partner with a sexually transmitted infection
• All pregnant women under 25
• Retesting of all women about 3 months after treatment
• Consideration of rectal chlamydia testing based on reported sexual behaviours

The bottom line

Pelvic inflammatory disease (PID) can lead to both chronic pain and infertility. Subclinical PID may also pose a greater risk to fertility, because it often goes undetected. Moreover, the diagnostic tools for subclinical PID are not clear-cut until a woman presents with unexplained infertility or tubal blockage. Sexually transmitted infections are the most common cause of PID and can often be asymptomatic. Getting tested for STIs (and encouraging any sexual partners to do the same) and using protection such as condoms are two of the best ways to protect yourself against PID.

Finally, finding a specialised and experienced gynaecologist for early detection and treatment of the disease is key to avoiding future effects of the disease on your fertility. To find out more about pelvic inflammatory disease and its treatment, contact the Centre for Reproductive Medicine and Fetal Medicine – Dr. Alexandros Traianos for a consultation.